Genomes and Genes
VIRULENCE IN ENTEROAGGREGATIVE E COLI
Principal Investigator: James Nataro
Affiliation: University of Maryland
Abstract: Enteroaggregative Escherichia coli (EAEC) is an increasingly recognized pathogen of human diarrhea. This organism has been implicated in sporadic diarrhea in developing and industrialized countries, in the persistent diarrhea syndrome in AIDS patients and children in the developing world, in traveler's diarrhea, and in various diarrheal outbreaks. The PI discovered this pathotype of diarrheagenic E. coli and has been the leader in describing the pathogenesis and epidemiology of this organism, This is a competing continuation of our fundamental work on the pathogenesis of EAEC infection. Overall, our objectives are to advance knowledge of EAEC pathogenesis, to better define true EAEC pathogens, to refine diagnostic methods and to identify protective immunogen. The three aims of this proposal seek to extend the most important and promising aspects of the work funded under the current award. Aim 1: Characterization of EAEC adhesion-Aggregation is the defining characterization of EAEC. Our observations suggest that aggregative adherence (AA) is a prelude to biofilm formation, which occurs in vivo and which can be modeled in vitro. In this aim, we will further elucidate fundamental aspects of EAEC adherence. Aim 2: The Regulation of EAEC virulence- AggR is a highly prevalent and conserved activator of AAF expression. However, nothing else is known of the regulation of EAEC virulence. Beginning with AggR, we will expand our studies of EAEC gene regulation. Aim 3: Reconstructing EAEC-We will use in vitro organ culture and T84 cell models of EAEC infection to answer the question: what genes are necessary and sufficient to confer the effects that we observe? The work under this award will greatly advance the current state of knowledge of EAEC and will result in the identification of pathogenetic mechanisms, of diagnostic reagents and in vaccine candidates.
Funding Period: 2000-08-01 - 2005-05-31
more information: NIH RePORT
- Enteroaggregative Escherichia coli: surface protein dispersin increases bacterial uptake of ciprofloxacinNinell P Mortensen
Biological and Nanoscale Systems Group, Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA Center for Aerosol and Nanomaterials Engineering, RTI International, Research Triangle Park, NC 27709, USA
Int J Antimicrob Agents 42:462-5. 2013....
- Bacterial serine proteases secreted by the autotransporter pathway: classification, specificity, and role in virulenceFernando Ruiz-Perez
Department of Pediatrics, School of Medicine, University of Virginia, P O Box 800326, MR4 Room 4012C, 409 Lane Road, Charlottesville, VA, 22908, USA
Cell Mol Life Sci 71:745-70. 2014..Here, we discuss their classification, substrate specificity, and potential roles in pathogenesis. ..
- Enteroaggregative Escherichia coli strain in a novel weaned mouse model: exacerbation by malnutrition, biofilm as a virulence factor and treatment by nitazoxanideDavid T Bolick
Center for Global Health, Division of Infectious Diseases and International Health, Department of Medicine, University of Virginia, Charlottesville, VA 22908, USA
J Med Microbiol 62:896-905. 2013....
- Enteroaggregative Escherichia coli disrupts epithelial cell tight junctionsMaura C Strauman
The Wistar Institute, Philadelphia, Pennsylvania, USA
Infect Immun 78:4958-64. 2010..Our results show that EAEC induces epithelial barrier dysfunction in vitro and implicates the AAF adhesins in this phenotype...
- Enteroaggregative Escherichia coli quantification in children stool samples using quantitative PCRIla Fernanda Nunes Lima
Institute of Biomedicine for Brazilian Semi Arid IBISAB and Clinical Research Unit, Federal University of Ceara, Fortaleza, Ceara, Brazil
APMIS 121:643-51. 2013..This new quantitative method provides a relatively simple means to quantify EAEC, which will likely be key to understanding the pathophysiology and impact of EAEC infection...
- Characterization of the AggR regulon in enteroaggregative Escherichia coliNicholas Morin
Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, Maryland, USA
Infect Immun 81:122-32. 2013..We show that mutations in these ORFs confer changes in bacterial surface properties. AggR coordinately controls expression of a large number of EAEC genes...
- The fimbriae of enteroaggregative Escherichia coli induce epithelial inflammation in vitro and in a human intestinal xenograft modelErik J Boll
Department of Microbiological Surveillance and Research, Statens Serum Institut, Denmark
J Infect Dis 206:714-22. 2012..Although previous studies report on the inflammatory aspects of EAEC pathogenesis, the mechanisms by which EAEC trigger these events are not well understood...
- Origins of the E. coli strain causing an outbreak of hemolytic-uremic syndrome in GermanyDavid A Rasko
University of Maryland School of Medicine, Institute for Genome Sciences and Department of Microbiology, Baltimore, USA
N Engl J Med 365:709-17. 2011..coli strains. Preliminary genetic characterization of the outbreak strain suggested that, unlike most of these strains, it should be classified within the enteroaggregative pathotype of E. coli...
- Serine protease autotransporters from Shigella flexneri and pathogenic Escherichia coli target a broad range of leukocyte glycoproteinsFernando Ruiz-Perez
Center for Vaccine Development and Program of Comparative Medicine, Department of Pathology, University of Maryland School of Medicine, Baltimore, MD 21201, USA
Proc Natl Acad Sci U S A 108:12881-6. 2011..In the guinea pig keratoconjunctivitis model, a Shigella pic mutant induced greater inflammation than its parent strain. We suggest that the class-2 SPATEs represent unique immune-modulating bacterial virulence factors...
- Shigella enterotoxin-2 is a type III effector that participates in Shigella-induced interleukin 8 secretion by epithelial cellsMauricio J Farfan
Centro de Estudios Moleculares, Departamento de Pediatria, Hospital Luis Calvo Mackennna, Facultad de Medicina, Universidad de Chile, Santiago, Chile
FEMS Immunol Med Microbiol 61:332-9. 2011....
- Effects of the plasmid-encoded toxin of enteroaggregative Escherichia coli on focal adhesion complexesRenato E Cappello
Institutional Program in Molecular Biomedicine, National School of Homeopathy and Medicine, Instituto Politecnico Nacional, Mexico City, Mexico
FEMS Immunol Med Microbiol 61:301-14. 2011..Finally, we show that in vitro tyrosine-dephosphorylated FAK was susceptible to Pet cleavage. These data suggest that mechanisms other than spectrin redistribution occur during Pet intoxication...
- Short report: high prevalence of serine protease autotransporter cytotoxins among strains of enteroaggregative Escherichia coliNadia Boisen
Department of Bacteriology, Mycology and Parasitology, Statens Serum Institut, Copenhagen, Denmark
Am J Trop Med Hyg 80:294-301. 2009..coli pathotypes rarely harbored a cytotoxic SPATE gene. SPATEs may be relevant to the pathogenesis of both EAEC and Shigella spp...
- Virulence characteristics and the molecular epidemiology of enteroaggregative Escherichia coli isolates from travellers to developing countriesDavid B Huang
Baylor College of Medicine, Division of Infectious Diseases, Houston, TX, USA
J Med Microbiol 56:1386-92. 2007....
- Measuring cell surface elasticity on enteroaggregative Escherichia coli wild type and dispersin mutant by AFMM A Beckmann
UT ORNL Graduate School of Genome Science and Technology, The University of Tennessee, Knoxville, 37996 0840, USA
Ultramicroscopy 106:695-702. 2006..This work represents an initial step in efforts to understand the pathogenic role of the dispersin protein in the wild-type bacteria...